Some might argue that very little could be drawn from such a facile victory, but here are some conclusions from Dublin's 27-point victory.

Life begins at 70 for Kevin McManamon

Perhaps aptly for a soldier of St Jude’s, McManamon has come to be recognised as Dublin’s patron saint of hopeless cases; the fire-fighter who is summoned from his sideline station, blue-lights flashing, to hose down the first hint of crisis.

A sequence of freeze-frames detailing the serial substitute's most famous emergency response – that goal for the ages against Kerry in 2011 that prompted a Vesuvian eruption of renewed hope on Hill 16 – takes pride of place on the walls of many of the city’s watering-holes.

It is a strange kind of glory and not one that has remotely sated the competitive furies that burn within McManamon; a league mainstay for the past five years – he scored five points from play in a losing tour de force against Cork in 2011 – he has, as he lamented in the build-up to this game, started scarcely half a dozen championship ties.

Life as Dublin’s defibrillator, the go-to guy for a supply of the therapeutic dose of electrical energy that prevents the Leinster giants from flatlining, is one Kevin Mac wishes to leave behind. He craves a first team role.

Though Jim Gavin has a legion of A-list attacking options, McManamon’s worker-ant philosophy, his direct running, a capacity to breathe in the most claustrophobic surrounds and create space for others presented a robust case for a starting slot here.

He thrived in sharing the playmaker role with the exceptional Ciaran Kilkenny, scoring two points and revelling as the launch pad for the Dublin rocket.

The 28-year-old will hope it might yet be sufficient to elevate the 28-year-old to the Dublin equivalent of La Cosa Nostra’s “made men”, a genuine 70-minute championship option.

Paul Flynn steps over the longford goalkeeper Paddy Collum after scoring the second Dublin goal

Dublin success lures the green-eyed monster from his lair

Like bird flu or volcanic ash-cloud, the first summer unleashing of Dublin might tends to provoke hysterical mutterings of Armageddon.

The paint was hardly dry on victory before the first tiresome split-the-county-in-two-or-football-is-doomed polemics were rolled down the Croke Park gangplank.

So let’s have some perspective here: Dublin have won three All-Irelands in the past 31 years. In that same period Kilkenny (12) Kerry (10), Cork (10, six hurling, four football), Meath and Tipp (four each) have enjoyed more senior success.

Yet nobody has ever Colm O’Rourke confronting Brian Cody with a suggestion about severing Kilkenny into two: The Black; and the Amber.

As for the rumours of underage hegemony: Dublin have won one minor football All-Ireland in Bernard Brogan’s lifetime.

Ciaran Whelan is among the most celebrated players to have worn the Sky Blue uniform. His county career endured for 15 summers. Not only did the Raheny colossus never conquer Everest, he never played in an All-Ireland final.

Dublin are overdue a road trip

Longford were reduced to the doomed role of an isolated wildebeest calf that inadvertently strays into a domain of a ravenous pride of jungle cats. All that was missing as they were torn asunder was the David Attenborough voiceover.

The Dubs were eight points up within eight minutes. There were some people on the pitch who thought it was all over. Sadly they included the 30 players.

It would be absurd to suggest Longford – though they pushed Dublin to the brink at Pearse Park in 2006, having been savaged by the same opposition at Croker 12 months earlier - might have reversed the 26 point margin with home advantage.

But for a sense of occasion asking Dublin to travel would have been transformative; though there were 33,544 in the Big House, it was more library than bear-pit.

Jim Gavin is happy to take the Dubs on the road; Hill 16 yearns to go on tour. All that is required now is for the Leinster Council delegates to vote for change.

Dublin might boast more strength in depth than any team in football history

Put this group with goalkeeper Stephen Cluxton and you have a hugely formidable team: For varying reasons though, none of those 14 outfield players – a group including two Footballers of the Year and a quintet of All Stars – started today’s game.

Yet without them – and with all six starting forwards scoring by the 14th minute - Dublin reduced to road kill the only team in Ireland to go undefeated across the four divisions of play during the regular season of the league.

Significantly Bernard Brogan – looking as menacing as at any time since his 2010 Footballer of the Year season - contributed 1-6 from play to the Sky Blue blitzkrieg.

The main course was served prior to the starter

What’s the fun in a whodunit where everybody knows the perpetrator before the first ad break?

Dublin were no more likely to lose to Longford than Sepp Blatter was to be found selling the Big Issue on Jones’ Road. Somebody intent on having a straight bet on the Sky Blues would have needed to invest €200 to win a solitary euro.

The notion of the game as a contest barely outlived the national anthem.

Logically the hurling collision of Galway and Dublin – featuring two teams with genuine All-Ireland aspirations, always certain to be competitive and which ended in a nail-biting draw - should have been the headline act rather than the curtain raiser.